| 摘要 |
<p>PROBLEM TO BE SOLVED: To display with halftone brightness by digital control by controlling the pulse width in applying a pulse to a liquid crystal material for a period during which the liquid crystal does not respond. SOLUTION: A pair of TFT's that constitute a modified inverter are formed between signal lines Y1 and Y2, and between Y2 and Y3, respectively, in parallel to signal lines X1 and X2. A matrix construction using such C/TFT's is formed. By repeating such a structure in right-to-left and upper-to-lower, a liquid crystal display device having a large number of pixels such as 640×480 or 1,280×960 can be produced. Gradation display of 256 levels or more is possible by displaying gradation with purely digital control, not applying any analog signal at all. Since the display is operated in a perfectly digital manner, gradation ambiguity due to characteristics variation of TFT's is perfectly eliminated, and extremely uniform gradation display is possible even though there are some characteristics variations among the TFT's.</p> |
